The gunmen left a notice on the EU office's door that the building would remain closed until Europeans apologize to Muslims, many of whom consider the cartoons offensive.

Muslims consider it sacrilegious to produce a likeness of the Prophet Mohammad. CNN has chosen to not show the cartoons out of respect for Islam.

Masked members of the militant groups Palestinian Islamic Jihad and Al Aqsa Martyrs Brigades, the armed wing of the Palestinians' former ruling party, Fatah, fired bullets into the air, and a man read the group's demands. (Watch masked gunmen demand an apology -- 2:48)

Palestinian officials said the gunmen were threatening to kidnap European workers if the European Union did not apologize.

A similar demonstration was held Monday in front of the same EU building to protest the first publication of the 12 drawings in September by the Danish newspaper Jyllands-Posten.

One of the images shows Mohammad wearing a turban shaped like a bomb with a lit fuse.

The caricatures have sparked protests in other parts of the Muslim world. Iraqis urged their government Wednesday to cut diplomatic ties with Denmark and Norway, where a publication reprinted the drawings last month. (Full story)

Danish Prime Minister Anders Fogh Rasmussen said the issue had gone beyond a feud between Copenhagen and the Muslim world and now centered on Western free speech versus taboos in Islam, which is the second religion in many European countries.

On Wednesday, two other European newspapers -- Die Welt in Berlin, Germany, and France Soir in Paris -- published the cartoons. Both papers said they were printing the drawings in solidarity with Jyllands-Posten, citing the right to publish them in a free society with a free press.

France Soir ran the cartoons under the headline, "Yes, One has the Right to Caricature God."

Le Monde reported that the publisher, Raymond Lakah, who is described as Franco-Egyptian, issued a statement saying he fired Lefranc as president and director of the newspaper in "a strong sign of respect to the intimate convictions and beliefs of each individual."

The statement continued, "We present our regrets to the Muslim community and to all people who have been shocked or made indignant by this publication."

Distribution of that edition of France Soir was blocked in Morocco and Tunisia because of the cartoons, Le Monde said.

The papers reprinting the cartoon were not limited to those published in Europe. The Jordanian tabloid Shihan also published them and urged Muslims to "be reasonable" in an accompanying editorial.

The editorial, written by Editor Jihad Momeni -- a former Jordanian senator -- asked: "Who offends Islam more? A foreigner who endeavors to draw the prophet as described by his followers in the world, or a Muslim with an explosive belt who commits suicide in a wedding party in Amman or elsewhere."

A spokesman for Shihan said Momeni had been fired.

Jordan, which has numerous laws against defiling religion and disturbing civil order, was the site of a November suicide attack that killed 57 people attending a wedding party in Amman.

The Arabic-language news channel Al-Jazeera has broadcast a report with the cartoons heavily distorted.